Tony
07-14-2002, 10:30 PM
I've got an unusual setup on my 302, compliments of the previous owner. Instead of a thermostat he built a "Y" shaped deflector to fit in the housing (see very elementary drawing), probably to divert more water to the starboard exhaust?
As a result, my temp guage claims my engine is running at 110 degrees, which is itself probably a false reading because of the cool water being deflected into the manifold by the "Y" deflector and swirling around the sensor(see other bad drawing). My engine guy reminds me that I need to operate the engine hot enough to "seal the head gaskets". Others have also told me that 110 is way too cool for optimum performance and longevity.
With the lake water supply being teed off like it is, another undesirable feature of this plumbing setup is that my port exhaust is being cooled by mostly lake water, with the other side having hot engine water passed thru it. Having two different temps on each side of the engine, I am told, is also undesirable.
While experimenting, I installed a thermostat, which failed to even open due to (I'm guessing) the cool lake water passing behind it thru the thermostat housing, giving it a false reading below the 160 degrees needed to open it.
So, to remedy and be able to use a thermostat, I am thinking of doing the following. Please feel free to critique my plans, as I am pretty much hypothesizing (guessing) as to the solution to this problem!
I plan on using a tee at the inlet for each exhaust instead of the current elbow, and will feed them with two sources of water. One source will be from the secondary raw water supply line, probably sized down a bit so as not to rob any pressure from the line feeding the engine water pump. Then I will send the engine water coming from the manifold thru the thermostat housing both ways, into each exhaust evenly.
BTW...what is the function of the small bypass line going from the engine water pump to the top of the manifold? (See pic)
http://www.donzi.net/photos/tsporer13612.jpg
http://www.donzi.net/photos/tsporer1961.jpg
http://www.donzi.net/photos/tsporer1964.jpg
As a result, my temp guage claims my engine is running at 110 degrees, which is itself probably a false reading because of the cool water being deflected into the manifold by the "Y" deflector and swirling around the sensor(see other bad drawing). My engine guy reminds me that I need to operate the engine hot enough to "seal the head gaskets". Others have also told me that 110 is way too cool for optimum performance and longevity.
With the lake water supply being teed off like it is, another undesirable feature of this plumbing setup is that my port exhaust is being cooled by mostly lake water, with the other side having hot engine water passed thru it. Having two different temps on each side of the engine, I am told, is also undesirable.
While experimenting, I installed a thermostat, which failed to even open due to (I'm guessing) the cool lake water passing behind it thru the thermostat housing, giving it a false reading below the 160 degrees needed to open it.
So, to remedy and be able to use a thermostat, I am thinking of doing the following. Please feel free to critique my plans, as I am pretty much hypothesizing (guessing) as to the solution to this problem!
I plan on using a tee at the inlet for each exhaust instead of the current elbow, and will feed them with two sources of water. One source will be from the secondary raw water supply line, probably sized down a bit so as not to rob any pressure from the line feeding the engine water pump. Then I will send the engine water coming from the manifold thru the thermostat housing both ways, into each exhaust evenly.
BTW...what is the function of the small bypass line going from the engine water pump to the top of the manifold? (See pic)
http://www.donzi.net/photos/tsporer13612.jpg
http://www.donzi.net/photos/tsporer1961.jpg
http://www.donzi.net/photos/tsporer1964.jpg